7861865 has 16 divisors (see below), whose sum is σ = 10354176. Its totient is φ = 5683200.

The previous prime is 7861853. The next prime is 7861897. The reversal of 7861865 is 5681687.

It is not a de Polignac number, because 7861865 - 2⁴ = 7861849 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11945 + ... + 12585.

It is an arithmetic number, because the mean of its divisors is an integer number (647136).

Almost surely, 2^7861865 is an apocalyptic number.

It is an amenable number.

7861865 is a deficient number, since it is larger than the sum of its proper divisors (2492311).

7861865 is a wasteful number, since it uses less digits than its factorization.

7861865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 880.

The product of its digits is 80640, while the sum is 41.

The square root of 7861865 is about 2803.9017457821. The cubic root of 7861865 is about 198.8421852592.

The spelling of 7861865 in words is "seven million, eight hundred sixty-one thousand, eight hundred sixty-five".